To find Braille, Go to Pacifilodge, and surf to the fast current. try to stay over to the left, but near the center slightly, and keep going in that direction until fou fing a calm spot where you can use Dive. Follow the underwater trench, and you will find a wall with Braille on it.
There are certain websites that have Braille decoders on them. Go there if you don't already have a Braille decoder.
Hey, I'm a ghost, why can't I walk through walls?